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排序方式: 共有598条查询结果,搜索用时 15 毫秒
591.
592.
J. Peter Rosenfeld Xiaoqing HuElena Labkovsky John MeixnerMichael R. Winograd 《International journal of psychophysiology》2013
In this review, the evolution of new P300-based protocols for detection of concealed information is summarized. The P300-based complex trial protocol (CTP) is described as one such countermeasure (CM)-resistant protocol. Recent lapses in diagnostic accuracy (from 90% to 75%) with CTPs applied to mock crime protocols are summarized, as well as recent enhancements to the CTP which have restored accuracy. These enhancements include 1) use of performance feedback during testing, 2) use of other ERP components such as N200 in diagnosis, 3) use of auxiliary tests, including the autobiographical implicit association test, as leading to restored diagnostic accuracy, and 4) a study of the mechanisms underlying CMs. A novel, doubly efficient version of the CTP involving presentation of two probes in one trial is described as a new way to improve accuracy to levels above 90% in mock crime situations. Finally, a thorough analysis of the legal issues surrounding use of the CTP in U.S. is given. 相似文献
593.
Using an immunoperoxidase technique that permits optimal antigen localization at the light microscope level, we have detected two platelet alpha-granule constituents and three platelet membrane glycoproteins in mouse bone marrow megakaryocytes and in murine megakaryocyte colonies grown in soft agar culture for three to seven days. Using polyclonal antibodies prepared against human platelet proteins, we have demonstrated labeling for von Willebrand factor, fibrinogen, and the membrane glycoproteins IIIa and GMP-140 in both bone marrow megakaryocytes and megakaryocyte colonies after seven days of culture. Using monoclonal antibodies to membrane glycoproteins IIb and GMP-140, we have demonstrated label in mouse bone marrow megakaryocytes. Granulocyte and macrophage colonies were negative for each of these markers. Murine bone marrow megakaryocytes and megakaryocyte colonies demonstrated a similar enzyme histochemical pattern: weakly positive for alpha-naphthyl acetate esterase and negative for chloroacetate esterase. These data indicate that megakaryocytes grown in soft agar culture express many of the same glycoproteins as bone marrow megakaryocytes. Furthermore, the ability of antibodies directed against human platelet membrane glycoproteins to identify murine megakaryocyte glycoproteins indicates that these constituents have been highly conserved during evolution. 相似文献
594.
595.
Johnson TS O'Neill AC Motarjem PM Amann C Nguyen T Randolph MA Winograd JM Kochevar IE Redmond RW 《The Journal of surgical research》2007,143(2):224-229
BACKGROUND: Photochemical tissue bonding (PTB) is a novel tissue repair technique that uses visible light and a photosensitizing dye to crosslink proteins on tissue surfaces. This technique has been successfully demonstrated in a number of tissue repair models. An ideal nerve repair technique would be atraumatic and avoid placement of foreign bodies at the repair site. The epineurium is suited to photochemical repair as it is thin, translucent and has a relatively high collagen content. This study was designed to determine if PTB could be successfully applied in a peripheral nerve repair model. MATERIAL AND METHODS: Forty Sprague Dawley rats underwent transection of the sciatic nerve. Animals were then randomized to four treatment groups; epineurial suture repair, epineurial cuff with PTB, epineurial cuff alone, and no repair. Functional recovery was assessed at 10 day intervals using walking track analysis and sciatic function index calculations. At 90 days postoperatively animals were sacrificed and sciatic nerves harvested for histology and histomorphometry. RESULTS: Functional recovery in the suture repair and epineural cuff with PTB groups were not significantly different (-70.6 +/- 17.8 versus -76.9 +/- 10.3, P = 0.64) at 90 days postrepair. Histology showed good axonal regeneration with all repair techniques. Histomorphometric analysis found no significant difference between the repair groups. CONCLUSIONS: This study illustrates that peripheral nerves can be successfully repaired using a photochemical tissue bonding technique with results similar to those achieved with the current gold standard. With further development and refinement PTB may prove a useful tool in peripheral nerve repair. 相似文献
596.
Sanders JE; Pritchard S; Mahoney P; Amos D; Buckner CD; Witherspoon RP; Deeg HJ; Doney KC; Sullivan KM; Appelbaum FR 《Blood》1986,68(5):1129-1135
One hundred forty-two patients between the ages of 1 and 17 years who survived disease-free more than 1 year after marrow transplantation for hematologic malignancy had growth and development evaluations from one to 14 years posttransplant (median 4 years). Prior to transplant all children received multiagent chemotherapy and 55 also received central nervous system irradiation, but none had growth and development evaluations. Marrow transplant preparation included high-dose chemotherapy and total body irradiation (TBI) given as a single dose of 9.2 to 10.0 Gy (79 patients) or as fractionated doses of 2.0 to 2.25 Gy/d for six to seven days (63 patients). After transplant abnormal thyroid function was present in 39%. Stimulated 11-desoxycortisol levels were subnormal in 24% of patients evaluated. Growth hormone (GH) deficiency was present in 17 of 25 children who received previous cranial irradiation. Partial GH deficiency was present in 4 of 25 who received previous cranial irradiation and in 6 of 18 who had not received cranial irradiation. Height velocity was decreased in all patients. After transplant, height was significantly influenced by chronic graft-v-host disease and single-dose TBI. Sixty-eight percent had delayed development of secondary sexual characteristics. Gonadal failure occurred in nearly all who were postpubertal at transplant. While it is not possible to determine how many of these endocrine abnormalities occurred as a result of treatment administered prior to transplantation, these data do demonstrate that children who become long-term survivors after marrow transplantation for hematologic malignancy have endocrine abnormalities that adversely affect growth and development. 相似文献
597.
Roeb E. Purucker E. Gartung C. Geier A. Jansen B. Winograd R. 《Scandinavian journal of gastroenterology》2013,48(8):878-885
Background: Extrahepatic cholestasis by biliary obstruction induces an acute phase reaction in the liver. It is a complex process involving cytokines, hormones and growth factors. To determine whether the regulation of acute phase proteins (APP) in cholestasis depends on glutathione (GSH), the effect of buthionine sulfoximine-induced (BSO-induced) GSH depletion on the expression of various APP was studied. In addition, we determined the influence of hepatoprotective bile acids on hepatic APP and underlying cytokine events. Methods: Liver samples of bile-duct-ligated or sham-operated rats were examined. mRNA expression was quantified by densitometric analysis of Northern blots. Results: Expression of APP increased 2-5-fold in bile-duct-ligated rats as compared to sham-operated controls. This acute phase reaction remained similar independently of whether cholestasis occurred for 5 days or 3 weeks. In contrast to ! 2-macroglobulin and tissue inhibitor of metalloproteinases-1 (TIMP-1), mRNA levels of both # -fibrinogen and haptoglobin were significantly up-regulated after GSH depletion by BSO in cholestasis. Feeding of ursodeoxycholic and iso-ursodeoxycholic acid markedly down-regulated ! 2-macroglobulin and TIMP-1 expression in cholestasis but did not affect overexpression of # -fibrinogen and haptoglobin. Cholestasis leads to an increased APP expression accompanied by an increased expression of inflammatory cytokines (IL-6, TNF- ! ). After feeding of hydrophilic bile acids, increases in inflammatory cytokines were abrogated. Conclusions: We show that GSH is involved in the acute phase reaction during obstructive cholestasis. In addition, bile acids might selectively ameliorate the acute phase response by reducing expression of the APP not affected by GSH depletion ( ! 2-macroglobulin and TIMP-1). 相似文献
598.
Deepak Pakalapati Shilpi Garg Sheetal Middha Abhishek Kochar Amit Kumar Subudhi Boopathi Pon Arunachalam Sanjay Kumar Kochar Vishal Saxena RP Pareek Jyoti Acharya Dhanpat Kumar Kochar Ashis Das 《Asian Pacific journal of tropical medicine》2013,6(5):346-351
ObjectiveTo evaluate microscopy, OptiMAL® and multiplex PCR for the identification of Plasmodium falciparumm (P. falciparum) and Plasmodium vivax (P. vivax) from the field isolates of Bikaner, Rajasthan (Northwest India).MethodsIn this study, a multiplex PCR (P. falciparum and P. vivax) was further developed with the incorporation of Plasmodium malariae (P. malariae) specific primer and also a positive control. The performance of microscopy, plasmodium lactate dehydrogenase (pLDH) based malaria rapid diagnostic test OptiMAL® and 18S rRNA gene based multiplex PCR for the diagnosis of P. falciparum and P. vivax was compared.ResultsThe three species multiplex PCR (P. falciparum, P. vivax and P. malariae) with an inbuilt positive control was developed and evaluated. In comparison with multiplex PCR, which showed the sensitivity and specificity of 99.36% (95% CI, 98.11%–100.00%) and 100.00% (95% CI, 100.00%–100.00%), the sensitivity and specificity of microscopy was 90.44% (95% CI, 88.84%–95.04%) and 99.22% (95% CI, 97.71%–100.00%), and OptiMAL® was 93.58% (95% CI, 89.75%–97.42%) and 97.69% (95% CI, 95.10%–100.00%). The efficiencies were 99.65%, 95.10% and 95.45% for multiplex PCR, microscopy and OptiMAL®, respectively.ConclusionsOur results raise concerns over the overall sensitivities of microscopy and OptiMAL®, when compared to the multiplex PCR and thus stress the need for new molecular interventions in the accurate detection of the malarial parasites. This further highlights the fact that further developments are needed to improve the performance of rapid diagnostic tests at field level. 相似文献